Question

a 1582 kg car is moving at 72.9 kn/h down a highway when the driver sees a turtle in the road. not wanting to hit it, the driver slows the car down to 37.9 kn/h over a distance of 26.3 m.

what force (in newtons) is necessary to slow down the car?

Answer 1

Here first we will use

v^{​​​​​​2}=u^{​​​​​​2}+2as

v-final speed. ,. u-intial speed , a- acceleration , s - distance travelled

( 37.9×5/18)²=(72.9×5/18)² +2a×26.3

a=5.69 m/s^{​​​​​s2 (deaccleration)}

^{Force on car= mass× acceleration}

^{Force=1582×5.69=8999.61 N}